Peters Township police said the intruder went to the offices of Dr. Oliver Herndon in Waterdam Plaza just before 6 p.m.

"He produced a handgun, stuck it in her back and demanded money," Capt. Michael Yanchak said. The woman's reaction was "to scream and possibly to start sobbing, and that -- despite the fact that he told her to be quiet -- prompted the attention of the doctor who came down the hallway and confronted the suspect."

Herndon then became a potential target, as the gunman pointed the weapon directly at him, police said.

"The suspect demanded money and told the doctor it wasn't worth shooting him over the money," Yanchak said.

But Herndon told him that they had already made their bank deposit for the day, so there was no cash in the office.

"The confrontation continued with the doctor walking down the hallway, back toward the door and the suspect backing up," Yanchak said. "When they reached the waiting room, the suspect turned and fled."

No description is available for the masked intruder, who was said to be white with a slight build. He wore all-dark clothing, but witnesses reported one thing that could be seen through his mask.